Tandem Mass Tag

Tandem Mass day ( tandem atomic mass label ' TMT) is a biochemical method for the mass spectrometric determination of biomolecules such as proteins, DNA or RNA. The TMT used inter alia Isobarenmarkierung and tandem mass spectrometry. The test molecules are thereby provided with different markings, which are isobaric though (the same initial mass possess ), but in the tandem mass spectrometer of different weights and thus distinguishable fragments (specifically, reporter ions) result.

Principle

There are three variants of the TMT:

• TMTzero - without isotopic labeling on the day
• TMTduplex - isobaric pairs after labeling with an isotope
• TMTsixplex - an isobaric mass labels set of six with five different isotopes

The markers used ( engl. day ) included four areas, a ground reporter area, a cleavable linker region, a mass normalization area and a binding to the biomolecule reactive group. The various markings are chemically identical but have different isotopes in the mass reporter and the mass normalization area. In a molecular weight determination by gel electrophoresis, chromatography or mass spectrometry easier the various labels are indistinguishable. Only by further fragmentation tandem mass spectrometry show after disruption of the peptide bonds, the individual markers. The patents for TMT are owned by Proteome Sciences Plc. The chemical structure of the various marks are recorded in the database and processed with Unimod Mascot.